Glass fiber mat based asphalt shingles tend to be brittle and to crack upon handling in cold weather.
U.S. Pat. No. 4,328,147 discloses glass fiber mat based asphalt shingles wherein the asphalt composition is modified to reduce cold-weather brittleness and includes 52 to 99 percent oxidized asphalt, 1 to 8 percent oxidized polyethylene, and 0 to 40 percent unoxidized asphalt or saturant.